Multisensory Processes in the Mechanics of Hearing

项目摘要 视觉帮助我们倾听。例如，唇阅读有助于言语理解，而视觉线索被认为是 对学习如何定位声音至关重要。视听交互通常被认为是 这是一种皮层现象，但越来越多的证据表明， 早在皮质期之前在这个项目中，我们研究视觉对听觉处理的影响 在最早出现的时候：在耳朵里。 听觉通路具有一个鲁棒的系统，用于通过以下方式调制传入听觉信号的处理： 外毛细胞和中耳肌肉组织的运动动作。这些结构正在下降 大脑的控制，为视觉相关信号影响听觉处理提供了潜在的途径。 这个系统受眼睛运动的影响：我们最近报道了一个以前未知的 鼓膜的振荡，其被时间锁定到扫视的发生并且在没有 传递的声音。 我们假设，这种眼动相关的外周听觉效应的基础过程 处理在协调视觉和听觉空间信号的差异中起作用， 眼球运动我们将通过确定眼动特性决定了什么来检验这一假设 鼓膜振动的特性，在眼神经系统中， 这种效应的起源;以及与眼动相关的周边处理如何与 视觉和听觉空间映射的变化。 总之，这些实验将揭示大脑如何调整其听觉输入，以协调 视觉系统在听觉通路的入口处发现多感觉信号 代表了我们对范围和机制的理解的根本转变， 服务的多感觉整合，但也对什么是以前被认为是单峰处理。 这些发现将与听力障碍以及其他涉及视觉的疾病有关。 和听觉缺陷，如诵读困难、听觉处理障碍、梅尼埃病、自闭症， 精神分裂症和与年龄相关的认知障碍。

PROJECT SUMMARY Vision helps us hear. For example, lip reading aids speech comprehension, and visual cues are thought to be critical for learning how to localize sounds. Visual-auditory interactions are usually considered to be a cortical phenomenon, but mounting evidence suggests that cross-talk between sensory systems begins well before the cortical stage. In this project, we investigate visual influences over the auditory processing at the earliest point that they occur: in the ear. The auditory pathway has a robust system for modulating the processing of incoming auditory signals via the motoric actions of outer hair cells and middle ear musculature. These structures are under descending control from the brain, providing potential routes for visual-related signals to influence auditory processing. This system is affected by movements of the eyes: we have recently reported a previously unknown oscillation of the eardrum that is time locked to the occurrence of saccades and occurs in the absence of a delivered sound. We hypothesize that the processes that underlie this eye movement-related effect on peripheral auditory processing play a role in reconciling the disparities in visual and auditory spatial signals that accompany eye movements. We will test this hypothesis by determining what eye movement properties determine the properties of the eardrum oscillation, where in the oculomotor system commands that contribute to this effect originate; and how eye-movement related peripheral processing changes in conjunction with changes in the mapping between visual and auditory space. Together, these experiments will shed light on how the brain tunes its auditory input to coordinate with the visual system. The discovery of multisensory signals at the very gateway of the auditory pathway represents a fundamental shift in our understanding of the scope and mechanisms employed not only in service of multisensory integration, but also on what was previously supposed to be unimodal processing. The findings will be relevant to disorders involving hearing as well as other conditions that involve visual and auditory deficits, such as dyslexia, auditory processing disorder, Meniere's disease, autism, schizophrenia, and age-related cognitive impairments.